mmc: tegra: Configure default tap values

Set the default inbound timing adjustment tap value on reset and on
non-tunable modes.

The default tap value is not programmed on tunable modes because the
tuning sequence is used instead to determine the tap value.

Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>